drivers: usb: fsl: Implement Erratum A-009116 for XHCI controller

This adjusts (micro)frame length to appropriate value thus
avoiding USB devices to time out over a longer run

Signed-off-by: Nikhil Badola <nikhil.badola@freescale.com>

drivers/usb/host/xhci-dwc3.c

@@ -89,3 +89,9 @@ int dwc3_core_init(struct dwc3 *dwc3_reg)
 
 	return 0;
 }
+
+void dwc3_set_fladj(struct dwc3 *dwc3_reg, u32 val)
+{
+	setbits_le32(&dwc3_reg->g_fladj, GFLADJ_30MHZ_REG_SEL |
+			GFLADJ_30MHZ(val));
+}

drivers/usb/host/xhci-fsl.c

@@ -58,6 +58,9 @@ static int fsl_xhci_core_init(struct fsl_xhci *fsl_xhci)
 	/* We are hard-coding DWC3 core to Host Mode */
 	dwc3_set_mode(fsl_xhci->dwc3_reg, DWC3_GCTL_PRTCAP_HOST);
 
+	/* Set GFLADJ_30MHZ as 20h as per XHCI spec default value */
+	dwc3_set_fladj(fsl_xhci->dwc3_reg, GFLADJ_30MHZ_DEFAULT);
+
 	return ret;
 }
 

include/linux/usb/dwc3.h

@@ -109,7 +109,11 @@ struct dwc3 {					/* offset: 0xC100 */
 
 	u32 g_hwparams8;
 
-	u32 reserved4[63];
+	u32 reserved4[11];
+
+	u32 g_fladj;
+
+	u32 reserved5[51];
 
 	u32 d_cfg;
 	u32 d_ctl;
@@ -118,15 +122,15 @@ struct dwc3 {					/* offset: 0xC100 */
 	u32 d_gcmdpar;
 	u32 d_gcmd;
 
-	u32 reserved5[2];
+	u32 reserved6[2];
 
 	u32 d_alepena;
 
-	u32 reserved6[55];
+	u32 reserved7[55];
 
 	struct d_physical_endpoint d_phy_ep_cmd[32];
 
-	u32 reserved7[128];
+	u32 reserved8[128];
 
 	u32 o_cfg;
 	u32 o_ctl;
@@ -134,7 +138,7 @@ struct dwc3 {					/* offset: 0xC100 */
 	u32 o_evten;
 	u32 o_sts;
 
-	u32 reserved8[3];
+	u32 reserved9[3];
 
 	u32 adp_cfg;
 	u32 adp_ctl;
@@ -143,7 +147,7 @@ struct dwc3 {					/* offset: 0xC100 */
 
 	u32 bc_cfg;
 
-	u32 reserved9;
+	u32 reserved10;
 
 	u32 bc_evt;
 	u32 bc_evten;
@@ -191,10 +195,16 @@ struct dwc3 {					/* offset: 0xC100 */
 #define DWC3_DCTL_CSFTRST			(1 << 30)
 #define DWC3_DCTL_LSFTRST			(1 << 29)
 
+/* Global Frame Length Adjustment Register */
+#define GFLADJ_30MHZ_REG_SEL			(1 << 7)
+#define GFLADJ_30MHZ(n)				((n) & 0x3f)
+#define GFLADJ_30MHZ_DEFAULT			0x20
+
 #ifdef CONFIG_USB_XHCI_DWC3
 void dwc3_set_mode(struct dwc3 *dwc3_reg, u32 mode);
 void dwc3_core_soft_reset(struct dwc3 *dwc3_reg);
 int dwc3_core_init(struct dwc3 *dwc3_reg);
 void usb_phy_reset(struct dwc3 *dwc3_reg);
+void dwc3_set_fladj(struct dwc3 *dwc3_reg, u32 val);
 #endif
 #endif /* __DWC3_H_ */